Abstract

Even Mathematics subject is very popular among students, it often makes them scare. They do not realize that it is badly need to master a science. It is probably caused by the models of the teaching and learning process which is not linked to the daily activities and the type of assessment which only fulfills immediate needs. Based on the fact, therefore, the writer wants to apply the Math teaching through contextual teaching and leaning approach with portfolio model. This study was aimed at making instructional design for Mathematicss through contextual teaching and leaning approach with portfolio model. The research designed used is a developmental study. The procedure of the research was adapted from Thiagara Jan with some modification which consisted of 4 steps: define, design, develop, and disseminate. Finally it produced draft 1, draft II, draft III. The results of the developing instructional design were lesson plans, students’ worksheet, structured tasks, and achievement test. The implication of the research finding had given a good response both teachers and students. They like the model very much. Meanwhile the achievement test had shown that the validity of 4 numbers were high, 5 numbers were moderate, 15 numbers were low, and 4 others were very low. The reliability of the test paper was high.